Mole Concept and Stoichiometry
by Udayalakshmi Bhamidipalli
1. MF = (EF)n
2. VD = RMM/2
3. Gay Lussac's law
3.1. Gases react in volumes bearing simple whole no. ratio to each other and gaseous products.
3.2. Numericals - identify vol. ratio and calculate for given volume
3.3. identify limiting reagent if any when volume of unused gas/ composition of resulting mixture is asked.
4. Avogadro's law
4.1. Equal volumes of all gases - same no. of molecules.
4.2. VD = mass of certain vol of gas/ mass of same vol of H2
5. Empirical and molecular formula
5.1. Empirical formula - gives the simplest ratio of the atoms of elements in a compound.
5.2. Mol. formula - gives actual ratio of atoms of elements in a compound.
5.3. 1. Identify the elements
5.4. 2. note down % composition
5.5. 3. note down at. mass
5.6. 4. AR = %comp/at. mass
5.7. 5. SAR = AR/least AR
5.8. 6. Round off SAR to the closest whole no.
5.9. n = RMM/EFM
6. Percentage composition
6.1. Find RMM
6.2. Mass of element x 100 / RMM
7. Mass-mass and volume -volume relationship
7.1. Identify the compounds related
7.2. Find RMM of compounds if mass is given/ asked for
7.3. Remember to use stoichiometric coefficients from the balanced eqn.
7.4. If vol is given or asked, use molar volume, multiply with appropriate stoichiometric coefficient.
8. Mole concept
8.1. RMM - No. of times one molecule is heavier than 1/12th the mass of C - 12.
8.2. one mole
8.2.1. 22.4 litres = 22400cm3
8.2.2. 6.023 x 10^23 particles
8.2.3. 1 RAM/ 1 RMM in grams
8.2.4. same no. of particles as atoms in 12g C- 12
8.3. Molar volume
8.3.1. 22.4 litres = 22400cm3
8.3.2. volume occupied by 1mole of gas at STP